Electric car-lighting system.



H. (mo ELECTRIC GAR LIGHTING SYSTEM.

' APPLICATION FILED APB.2 9. 1907. 994,510.

Patented June 6, 1911'.

[Mr/V5855 wjamw v HUGO GROB, F ZURICH, SWITZERLAND.

ELECTRIC CAR-LIGHTING SYSTEM.

Specification of Letters IPatent.

Patented June 6, 1911.

Application filed April 29, 1907. Serial No. 371,002REISSUE To all whom it may concern: Be it known that I, HUGO GR B, a citizen of the Swiss Confederation, residing at Zurich, Switzerland, have invented a new and useful Electric Car-Lighting System;

and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification The subject of the present invention is anx apparatus for the electrical illumination of vehicles, the voltage of which is kept constant independently of the number of revow lutions and of'the amount of Current consumed in a purely electrical way, without the use of any mechanism, and the battery of which is automatically recharged during the running of the vehicle. Obviously the current generated by the system may be used also for heating the car, also for cooking, ventilating and other purposes.

The principle on which the pressure or tension is regulated is known and is as follows :When a continuous current generator is connected in parallel with an extraneous source of pressure, so that the compensatory current which is eventually roduced in the connecting conductors ffhws through an exciting coil, and in this way causes at least a portionof the excitation of the said generator, be it directly or through they medium of an excitingdynamo, the aforesaid continuous current dynamo possesses the property, as it is Well known, of

producing a pressure which is almost constant, independent of'the load and number of revolutions. It is necessary, however,

' thatthe generator or its exciting dynamo should be so constructed, that it requires "only a very small exciting force and the exciting coil should consist only of av few windings, so that a very slight difference of pressure in the exciting coil is sufficient to produce the full generator pressure even with the lowest number of revolutions employed. It is easy to understand, that the pressure of the generator cannot, under any circumstances, differ from the extraneous independent pressure by anamount greater than the-fall of pressure which the compensatory current, necessary for the production ofthc generator pressure produces in the 'erator.

lated in the manner hereinbefore described,

connecting conductor together with the exciting coil. The generator pressure is always slightly lower than the independent pressure, so that the latter supplies the exciting current. If 'now, from any cause the pressure produced by the generator rises, the difference ofpressure producing excitation will immediately fall and consequently. also the exciting current, and the dynamo pressure will therefore remain approximately constant, although the number of revolutions or the load may vary. The use of this pressure regulating method alone would not, however, lead to practically useful a paratus for the electrical illumination 0 vehicles; for this purpose a series of additional features are necessary.

The essential feature of the present invention consists in the combination of the above described pressure regulating method with a number of additional devices, whichalone enable this pressure regulating method to be used for illuminating vehicles, as will be fully set forth hereafter.

Figure 1 is a diagram of a vehicle lighting What 'is said herein may be applied 0bviously to heating, cooking, ventilating as well as to the application of the plant to other vehicles.

Like every other train lighting apparatus,

the present one also employes a storage battery which when the train is at a standstill supplies the illuminating current. Thisbattery must be recharged, while the train is running. p

As mentioned at the beginning of this specification, theregulaiziqon of pressure may be effected by means o my suitable extraneous source of pressure, or the existingbattery may be divided into two halves Z and Z one ofwhich is used to supply the independent extraneous pressure required for the regulation of the words it supplies the exciting current, while the other battery half is charged by the gen- The voltage of a generator, regucannot "be higher than the egtraneous -.;independent pressure, applied ,s to'flp'ppose the-pressure to be regulated at is to say ressure, in other in our case, not higher than the.- pressureiifof the half of the battery. which discharges itself by supplying the exciting compensatory current. The directly regulated pressure cannot therefore sufiice to charge the other half of the battery, since a higher pres- 5 sure is necessary for this purpose. In the present train 1i hting apparatus this higher pressure is pro uced in the following novel manner.

In Fig. 1 the lines G A A G show the entire armature winding of an ordinary continuous current generator. This armature winding may be continuous, as in an ordinary armature, or itmay consist of separate windings, each of which has a collector, and the said windings being" arranged in series. E is an exciting coil, which causes at leasta portion of the excitation of the generator, and which may be placed either directly in the magnetic circuit of the gener ator (Fig. 1) or in that of an exciting dynamo Q of the generator (Fig. 2). The extraneous independent pressure, 6.12.- the one half Z or Z of the battery, is connected to two terminals M of the generator, (the regulating exciting coil E being switched in between), between which terminals less than the entire number of armature conductors existing inthe generator is in action, so that there exist other machine terminals P, be-

tween which there exists a higher pressure than the directly regulated pressure. This higher pressure, which is likewise independ-.

ent of the number of revolutions, is used to charge the other half of the battery. k The armature reaction field may be eliminated with great advantage in the usual way, by compensation coils K, placed between the poles an'd'traversed by the armature current. The object of this is to obvi- 40 ate the self induction of the armature and thereby to protect the switch contacts from being burned.

The lighting current may be taken from the apparatus either at the terminals M, at discharging pressure or at the points P at battery charging pressure, but in the latter case a resistance must be placed in the lighting circuit, which resistance absorbs the difference between the charging pressure and the lighting pressure and is short-circuited,

vtvehen the lamps are fed directly by the bat ry.

The half of the battery which is being charged, receives its current, at a constant pressure, from the terminals P. In order that this charging current may not be too great, when the battery is empty, a resistance is permanently situated 1n the charging circuit. I

For the purpose of switching the machine into and out of the lighting circuit at a fixed speed of the train, I employ in mv system a centrifugal governor W, which also serves to exchange the halves of the battery atterevery stoppage. Figs. '1 to 5 show diagrammatically, in what manner this exchange of the batteries at ever stop age may be effected. Every time the alls o the centrifu al governor move apart, and every time, when they close together again, the ratchet wheel R continues to turn 90 in the same direction, thereby shifting the switches V at the commencement of a run to the left hand position, at the next stoppage again to the center, at the following run into the right hand position, on the subsequent stoppage again to the center, and so on. The changing over of the batteries is necessary to enable that half of the battery which had just supplied the exciting current to be re-charged. Fig. 3" shows a special example of construction of my train lighting a paratus. The armature B has two windings 61 and C separated from each other, each with its own collector. The extraneous independent pressure, which is supplied from one of the two halves of the battery, is switched on in opposition to one winding 0 only, while the other winding 0,, in series with the first, imparts to the chargi current of the other battery halt the.add1tional rise of pressure required for charging. The excitin coil placed between the winding C and t e exciting battery Z excites the generator B directly. The lighting circuit is joined up to the directly regulated pressure of the winding C The com ensating coil K is traversed both by the lighting and by the charging current, N denotes, as in Fig. 1, the

reducing rheostat in the charging conductor for preventing excessive chargingcurrents.

In the examples shown in Figs. 4 and 5 the generator armature B has only one winding with one collector, on the other hand, however, two pairs of brushes A A, and G Gr are provided. The brushes A A to which the exciting pressure is joined, embrace fewer armature conductors, than the brushes- G G, which supply the charging current.

In Fig. 4 the lighting current is taken from the low-tension brushes (A A in Fi 5 from the high tension brushes (Gr G In the latter case the lamps must have a resistance X switched on in front of them, when the train is running, such resistance being short circuited when the machine is switched ofl'. This may be effected, for instance, by causing the same mechanical motion, which connects the lamps at one time with .the battery and another time with the generator, to operate a short circuitin device placed parallel to the resistance The machine may be driven in any de- I sired manner, 0. g. off one of the axles of the carriage. t J 2 5 What Iclaim is 1. Car-lighting system, comprising a continuous current generator havlng two pairs of terminals one of which (the low tension pair) has a lower voltage than the other generator; and an exciting coil adapted to influence the magnitude of the pressure produced in the generator and inserted into the circuit connecting the low-tension terminals of the generator with the said extraneous source of constant voltage, substantially as described.

2. Gar-lighting system comprising a continuous current generator havin two armature windings with separate'co lectors and two pairs of terminals one of which, viz: the low-tension-pair, embraces only'one of the windings, while the other, viz: the high tension pair, embraces the two windings in series; an extraneous source of constant voltage connected in parallel with the low-ten sion terminals of the generator; a storage battery connected in parallel with the high tension terminals of the generator; and an exciting coil adapted to influence the magnitude of the pressure produced in the generator and inserted into the circuit connecting the low-tension terminals of the generator with the said extraneous source of constant voltage, substantially as'described.

3. Car-lighting system comprising a continuous current generator having two pairs of terminals one of which has a lower voltage than the other; a storage battery connected in parallel with the low-tension terminals of the generator; a storage battery connected in arallel with the high tension terminals 0? the generator; and an exciting coil adapted to influence the magnitude of the pressure produced in the generator and inserted into the circuit connecting the lowtension terminals of the generator with the first mentioned battery, substantially as described.

1. Car-lighting system comprising a continuous current generator having'two pairs of terminals one of which has a lower volt-' age than the other; an extraneous source of constant voltage connected in parallel with, the low tension terminals of the generator;

a stora e battery connectedfin parallel with the high tension terminals of the generator; and an exciting coil of the generator inserted into the circuit connecting the low-tension; terminals of the generator with the said extraneous source of constant voltage, substantially as described.

5. Car-lighting system comprising a continuous current generator havm two armature windin with separate co lectors and two pairs 0 terminals one of which, viz; the low' tension pair, embraces only one winding while the other, viz: the high ten-' sion-pan, embraces the two windings in series; a storage battery connectedin parallel with the low tension terminals of the generator; a storage battery connected in parallel with the high tension terminals of the generator; and an exciting coil of the generator inserted into the circuit connecting the low-tension terminals'of the generator with the first mentioned battery, substantially as described.

7 Y 6. Car-lighting system comprising a continuous current generator having a compensated armature reaction field and fltwo pairs of terminals one of which has a lower voltage than the other; an extraneous source of constant voltage connected in parallel with the low-tension terminals of the generator; a storage battery connected in parallel with the high-tension terminals-of the generator; an exciting coil adapted to illfluence the magnitude of the pressure produced in the generator and inserted into the circuit connecting the low-pressure terminals of the generator with the said extraneous source of constant voltage; means employed in the circuit connecting the high tension terminals with the battery for preventing an excessive current from arising in this circuit; and means for switching the generator into and out of the working circuit according to the speed of the generator, substantially as described.

7. Car-lighting system comprising a continuous current generator having a compensating armature reaction field and two pairs of terminals one of which has a lower voltage than the other; a storage battery connected in parallel with the low tenslon terminals of the generator; a storage battery connected in parallel with the high tension terminals of the generator; an exciting coil of the generatoiyinserted into the circuit connecting the low tension. terminals of the generator with the first mentioned battery;

means employed in the circuit connecting the high tension terminals with the battery for preventing an excessive current from arisingin this circuit; means for switching the generator into and out of its working circuit according to the speed of the generator; and means for periodically exchanging the connections of the two batteries, substantially as described.

8. Car-lighting system comprising a continuous" current generator having a compensated armature reaction field; two armature windin s with separate collectors and two pairs o? terminals one of which, viz: the low-tension pair embraces only one of the windings while the other, viz: the high tension pair, embraces the two windings in series; a stora e battery connected in parallel with the ow-tension terminals of the generator; a storage battery connected in parallel with the high tension terminals of the generator; an exciting coil of the generator, inserted into the circuit connecting with the first mentioned battery; a resistthe generator, substantial1y as descri ance inserted into the circuit connecting the In testimony whereof, I have signed my high-tension terminals with the second menname to this specification in the presence of 5 tioned battery; a centrifugal governor two subscribing witnesses.

adapted to switch the generator into and HUGO GROB out of the. working circuit according to the speed of the generator; and a reversing Witnesses: switch adapted to be operated by the said IIERMANN HUBER, 10 governor so as to exchange the connections A. LIEBEBKNECHT.

the low-tension terminals of the generator 1 of the two batteries after every stopp): e of 

